Low-friction abrasion-resistant plastic weatherstrip

ABSTRACT

An extruded all-plastic weatherstrip of the type having a rigid base insertable into a slot in a structure to be protected and a flexible weatherstrip portion protruding from the base into engagement with the edge of a door or window to be sealed, the base and weatherstrip portion being dual-extruded together to form a unitary structure, and the weatherstrip portion having partially embedded in its exposed wearing surface a series of spaced ribs of hard, low-friction, abrasion-resistant plastic material preferably also produced by multiple extrusion.

United States Patent Kessler 51 Aug. 22, 1972 [541 LOW-FRICTIONABRASION- RESISTANT PLASTIC WEATHERSTRIP [72] Inventor: Gerald Kessler,388 Cranberry Run,

Boardman, Ohio 44512 22 Filed: Sept. 28, 1970 21 Appl.No.: 76,137

[52] US. Cl. ..49/489, 156/244, 156/279, 161/146 [51] Int. Cl. ..E06b7/16 [58] Field of Search .49/489, 488, 498, 490, 495, 49/475, 485;277/231, 211, 227; 161/146-149; 156/244, 279

[56] References Cited UNITED STATES PATENTS 3,385,001 5/1968 Bordner..49/489 2,909,815 10/1959 Campo ..49/489 X '(IIIIII Mims et a1.l60/D1G. 8 Bus et a1. ..49/485 Primary Examiner-David J. WilliamowskyAssistant Examiner-Philip C. Kannan AttorneyMax L. Libman ABSTRACT Anextruded all-plastic Weatherstrip of the type having a rigid baseinsertable into a slot in a structure to be protected and a flexibleWeatherstrip portion protruding from the base into engagement with theedge of a door or window to be sealed, the base and Weatherstrip portionbeing dual-extruded together to form a unitary structure, and theWeatherstrip portion having partially embedded in its exposed wearingsurface a series of spaced ribs of hard, low-friction,abrasion-resistant plastic material preferably also produced by multipleextrusion.

3 Claims, 3 Drawing Figures Gerald essler LOW-FRICTIONABRASION-RESISTANT PLASTIC WEATHERSTRIP This invention is an improvementover and related to the application of the same inventor, Ser. No.620,036, now U.S. Pat. No. 3,535,824, filed Mar. 2, 1967, forAbrasion-Resistant Rigid-Flexible Weatherstrip, which discloses the sametype of Weatherstrip as the present invention, but employs a surfacingof fine discrete hard particles adhered to the wearing surface of theflexible Weatherstrip portion. The present invention provides animproved wearing surface with low friction which does not tend to becomedetached from the Weatherstrip in use and is simple and economical tomanufacture.

A basic problem with flexible plastic Weatherstripping is that when theflexible plastic is soft enough to conform to the surface which it isintended to seal, it is often too sticky to allow free movement of themember it is Weatherstripping, so that it becomes difficult to open orclose the door or window. Furthermore, in the common case ofpre-manufactured door and window frames, which are usually made ofextruded aluminum, the Weatherstripping is machine-inserted into a.pre-formed slot in the aluminum, and when the Weatherstrip material istoo soft and flexible, this operation may become very difficult, so thatit is advantageous for at least the base portion of the Weatherstrip tobe sufficiently hard and rigid to facilitate such insertion.

Still another problem is that the flexible portion of the Weatherstripoften tends to wrinkle or be somewhat wavy, and therefore does notengage the surface which it is intended to seal at all points. Thepresent invention provides a certain amount of rigid support for theflexible portion of the Weatherstrip, due to the series of ribs ofrelatively hard plastic material partially embedded in the surface ofthe flexible Weatherstrip, which tends to improve its longitudinalrigidity and straightness, while permitting sufficient lateral flexingfor proper sealing of 40 engaged surfaces, even when they are somewhatuneven.

The specific nature of the invention, as well as other objects andadvantages thereof, will clearly appear from a description of apreferred embodiment, as shown in the accompanying drawings, in which:

FIG. 1 is a transverse sectional view of one form of Weatherstrip;

FIG. 2 is a similar view of a slightly different form of Weatherstrip ina typical use situation; and

FIG. 3 is a similar view of still another form.

The only difference between the forms of Weatherstrip shown in theFigures, is that FIG. 1 shows the flexible Weatherstrip portion 2extending perpendicularly from the base 3, while in FIG. 2 the flexibleportion 2' extends at an angle from the base other than 90, which is atypical situation when the Weatherstrip is used with sliding doors andwindows, and is also shown in FIG. 3.

The Weatherstrip comprises a base portion 3 having an outer shell 4 ofrigid plastic and sufficient mechanical strength to support theWeatherstrip for attachment to any surface to be sealed, such as a doorjamb, windowsill, or edge of a door or window frame, as indicated at 6in FIG. 2. In a typical situation, the door or window to be sealed,which is indicated at 7 in FIG. 2,

slides in its own plane, and since the Weatherstrip must dow. TheWeatherstripping may also be fastened in any other suitable way such asby gluing or nailing, as is well known. The flexible Weatherstripportion 2 is joined at one edge to the base 4 in any suitable manner,but a preferred manner is to employ an interlocking connection such asindicated in FIG. 1 by the T-shaped configuration 5, where the top ofthe T is embedded in the hard base portion 4. Since the two elements areproduced by dual extrusion, that is, they are both extruded at the sametime through a suitable orifice configuration to produce the desiredcombined product, it is possible by well-known techniques to produce anydesired interlocking cross-section, and the one shown is only given byway of example, it being preferred, however, that an interlockingjunction be employed so that the junction between the soft and hardplastic is mechanically firm as well as being thermally fused together.

While the Weatherstrip is being extruded, the same dual extrusiontechnique is employed to also extrude a contact the surface which is tobe sealed, as shown at 7 in FIG. 2. Any suitable plastic material can beemployed, but vinyl plastic (PVC) is particularly suitable for this use,as it can be produced in any desiredrange of hardness within wide limitsas is well known in the art. In general, the same degree of hardness issuitable for the ribs 9 as for the base 4, and this also simplifiesproduction, since it does not require a different material to beemployed. The flexible vinyl plastic of the sealing portion 2 is made ofa material suitable for dual extrusion with the rigid; for example,flexible PVC with rigid PVC; EVA with polyethylene. The ribs 9 arespaced sufficiently apart to permit free lateral flexing of the sealingportion 2 or 2', but sufficiently close 5 together so that they take allor substantially all of the tively rigid ribs 9 tend to controlwrinkling or curving of the strip, and to produce the desiredstraightness of the sealing portion.

The base portion 6, which is typically also an extruded plastic element,can be of any suitable shapeslot, round, dovetail, diamond, etc. Adiamond-shaped base and slot are shown by way of example in FIG. 3, withcorresponding parts correspondingly numbered, but double-primed.

I claim:

longitudinally extending base portion or rigid plastic material ofsufficient mechanical strength to support the Weatherstrip in a slotbelow a surface to be sealed,

said base portion being in the form of an elongated strip,

b. a longitudinally extending tape-like strip of flexible plasticmaterial having one ,edge interlocked l. a) An extruded all-plasticWeatherstrip having a with and thermally fused to said base portion, andextending away from said base portion on one side thereof,

. the other edge of said flexible strip being free to at least one ofthe sides of the flexible strip near conform to a surface being sealedagainst the weather to provide a plurality of continuous sealingsurfaces along the entire length of the engaged portion.

2. The invention according to claim 1, said base strip having two sidesand two edges, said flexible strip being joined to said base strip alonga line between the two edges of the base strip, leaving both edges ofthe base strip free for insertion into a slot as the sole support forthe Weatherstrip.

3. The invention according to claim 2, the plane of said flexible stripbeing at an angle between 30 and to the plane of the base strip.

1. A) An extruded all-plastic weatherstrip having a longitudinallyextending base portion or rigid plastic material of sufficientmechanical strength to support the weatherstrip in a slot below asurface to be sealed, said base portion being in the form of anelongated strip, b. a longitudinally extending tape-like strip offlexible plastic material having one edge interlocked with and thermallyfused to said base portion, and extending away from said base portion onone side thereof, c. the other edge of said flexible strip being free toflex, d. at least one of the sides of the flexible strip near the frEeportion having a series of parallel, sapaced-apart,longitudinally-extending ribs of relatively rigid plastic materialpartially embedded in its surface and integrally united therewith, witha portion of each rib extending beyond the surface of the flexiblematerial to provide a series of smooth, hard low-friction ribs separatedby flexible material, said ribs being sufficiently close together sothat several of the ribs can engage and conform to a surface beingsealed against the weather to provide a plurality of continuous sealingsurfaces along the entire length of the engaged portion.
 2. Theinvention according to claim 1, said base strip having two sides and twoedges, said flexible strip being joined to said base strip along a linebetween the two edges of the base strip, leaving both edges of the basestrip free for insertion into a slot as the sole support for theweatherstrip.
 3. The invention according to claim 2, the plane of saidflexible strip being at an angle between 30* and 90* to the plane of thebase strip.